The present invention is directed to a process for preparing superalkalinized metallic detergent-dispersant compositions, useful as additives for lubricating oils, the additives per se, and to lubricating oils containing them.
British Pat. No. 1,015,769 discloses the preparation of detergent-dispersant compositions of high alkalinity having a base of alkylphenates and alkylbenzene sulfonates of alkaline earth metals by sulfurization of a mixture containing an alkylphenol, an alkaline-earth metal alkylbenzene sulfonate, a C.sub.8 -C.sub.18 monoalcohol, an alkaline-earth base and glycol, precarbonation of the sulfurized mixture, alkalinization of the precarbonated mixture by an alkaline-earth base, carbonation, and then elimination of the glycol and recovery of the detergent-dispersant.
Such a process has the drawback that it requires the use of a C.sub.8 -C.sub.18 monoalcohol, which must then be recycled in practically anhydrous form.
Furthermore, while such a process is satisfactory for the preparation of detergent-dispersant compositions containing a high proportion of alkylphenates, it cannot, however, be used for the preparation of detergent-dispersant compositions containing a high proportion of alkylbenzene sulfonates.
By the present invention, a process has been provided which makes it possible to prepare detergent-dispersant additives having a base of metallic alkylbenzene sulfonates and alkylphenates of a TBN (Total Basic Number-ASTM Standard D 2896) of more than about 200 in a simple and rapid manner, in the presence of alkylene glycol in only small quantity and in the absence of monoalcohol. The new process does not have the drawbacks of the prior art.
It is, therefore, an object of the present invention to provide novel detergent-dispersant compositions useful as additives for lubricating oils having a base of alkylbenzene sulfonates and sulfurized alkylphenates.
It is also an object of the present invention to provide a novel process for the preparation of detergent-dispersant compositions for use as additives in lubricating oils.
It is also an object of the present invention to provide lubricating oils containing the novel additives of the invention.
Other objects of the present invention will be apparent to those skilled in the art from the present description.